C# '@' before a String

It means to interpret the string literally (that is, you cannot escape any characters within the string if you use the @ prefix). It enhances readability in cases where it can be used.

For example, if you were working with a UNC path, this:

@"\\servername\share\folder"

is nicer than this:

"\\\\servername\\share\\folder"

It also means you can use reserved words as variable names

say you want a class named class, since class is a reserved word, you can instead call your class class:

IList<Student> @class = new List<Student>();

Prefixing the string with an @ indicates that it should be treated as a literal, i.e. no escaping.

For example if your string contains a path you would typically do this:

string path = "c:\\mypath\\to\\myfile.txt";

The @ allows you to do this:

string path = @"c:\mypath\to\myfile.txt";

Notice the lack of double slashes (escaping)